JavaScript | weakMap.get()

The weakMap.get() is an inbuilt function in JavaScript which is used to return a particular element from a object WeakMap.

Syntax:

weakMap.get(key);

Parameters: It accepts a parameter “key” which is the key of the element which is going to be returned from the object weakmap.



Return values: It returns the element which is associated with the particular key in the WeakMap object and it returns undefined if the key can not be found.

JavaScript code to show the working of weakmap() function:

Code #1:

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<script>
  
   // Creating a WeakMap() object
   const weakmap1 = new WeakMap();
     
   // Creating a key "key1"
   const key1 = {};
     
   // setting value 42 with key "key1" in the 
   // object weakMap
   weakmap1.set(key1, 42);
     
   // Getting the specified elements i.e, 42
   document.write(weakmap1.get(key1));
  
</script>

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Output:


42


Code #2:











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<script> 


  


   // Creating a WeakMap() object 


   const weakmap1 = new WeakMap(); 


     


   // Creating a key "key1" 


   const key1 = {}; 


     


   // Getting the specified elements 


   document.write(weakmap1.get(key1)); 


  


</script> 



















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Output:


undefined


Here output is undefined because the key “key1” has not been set at the end of the weakMap object.



          
          
          

          

    

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